Add merge_peers and always_emit_headings options to ChunkDoclingDocumentComponent

[ricofurtado]

Introduce two new options, merge_peers and always_emit_headings, to enhance the functionality of the ChunkDoclingDocumentComponent. These options allow for merging undersized chunks with shared metadata and emitting headings for empty sections, respectively.

Summary by CodeRabbit

• New Features
  • Added "Merge peers" option to merge undersized chunks with shared metadata (enabled by default).
  • Added "Always emit headings" option to emit headings for empty sections (disabled by default).

[coderabbitai]

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Walkthrough

Two new boolean input parameters (merge_peers and always_emit_headings) are added to the ChunkDoclingDocumentComponent with visibility logic that displays them only when HybridChunker is the active chunker. These parameters are passed to HybridChunker initialization during document processing.

Changes

Cohort / File(s)	Summary
New ChunkDoclingDocumentComponent inputs src/lfx/src/lfx/_assets/component_index.json, src/lfx/src/lfx/components/docling/chunk_docling_document.py	Added two new boolean inputs (merge_peers, always_emit_headings) with display names, descriptions, and default values. Extended build-config logic to show/hide these inputs when HybridChunker is active. Updated HybridChunker instantiation to receive these parameters from component state.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

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Important

Pre-merge checks failed

Please resolve all errors before merging. Addressing warnings is optional.

❌ Failed checks (1 error, 3 warnings, 1 inconclusive)

Check name	Status	Explanation	Resolution
Test Coverage For New Implementations	❌ Error	PR introduces new functionality (merge_peers and always_emit_headings parameters) without any corresponding test coverage.	Add unit tests for parameter validation and integration tests verifying HybridChunker receives correct parameters. Address API incompatibility of always_emit_headings parameter.
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.
Test Quality And Coverage	⚠️ Warning	PR adds two new boolean parameters to ChunkDoclingDocumentComponent but includes zero test files or test modifications.	Add unit tests validating parameter storage, visibility toggle logic, and HybridChunker instantiation; add integration tests for full chunk_documents() workflow.
Test File Naming And Structure	⚠️ Warning	The pull request adds two new component options (merge_peers and always_emit_headings) but includes no test files following standard naming conventions (test_*.py or *.test.ts).	Add test_chunk_docling_document.py with tests validating the new options are properly exposed, passed to HybridChunker, and handle edge cases including unsupported parameters.
Excessive Mock Usage Warning	❓ Inconclusive	No test files for ChunkDoclingDocumentComponent were found in the pull request to assess mock usage patterns.	Provide test file paths for ChunkDoclingDocumentComponent or clarify if this PR includes test coverage.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The pull request title clearly and accurately summarizes the main change: adding two new options (merge_peers and always_emit_headings) to the ChunkDoclingDocumentComponent.

✨ Finishing touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch chunk-docling-document-component-changes

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[github-actions]

Frontend Unit Test Coverage Report

Coverage Summary

Lines	Statements	Branches	Functions
	18.41% (5919/32150)	12.03% (3017/25069)	12.36% (855/6913)

Unit Test Results

Tests	Skipped	Failures	Errors	Time
2288	0 💤	0 ❌	0 🔥	31.642s ⏱️

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 35.22%. Comparing base (e10cdbf) to head (ffe701a).
⚠️ Report is 1 commits behind head on main.

❌ Your project check has failed because the head coverage (42.12%) is below the target coverage (60.00%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #11684      +/-   ##
==========================================
+ Coverage   35.20%   35.22%   +0.01%     
==========================================
  Files        1521     1521              
  Lines       72922    72923       +1     
  Branches    10936    10936              
==========================================
+ Hits        25674    25686      +12     
+ Misses      45853    45843      -10     
+ Partials     1395     1394       -1     

Flag	Coverage Δ
backend	55.70% <ø> (+0.04%)	⬆️
frontend	16.65% <ø> (-0.01%)	⬇️
lfx	42.12% <ø> (+0.01%)	⬆️

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see 9 files with indirect coverage changes

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[coderabbitai]

Actionable comments posted: 2

🤖 Fix all issues with AI agents

In `@src/lfx/src/lfx/_assets/component_index.json`:
- Line 64090: Summary: remove the unsupported always_emit_headings parameter and
input. Fix: in ChunkDoclingDocumentComponent remove the Message/Bool Input
definition for "always_emit_headings" from the inputs list and remove any
build_config toggles referencing "always_emit_headings" in update_build_config;
also remove the argument always_emit_headings=bool(self.always_emit_headings)
passed into the HybridChunker() instantiation inside chunk_documents (and any
uses of self.always_emit_headings). References to change: the inputs list entry
named "always_emit_headings", the update_build_config branch that sets
build_config["always_emit_headings"][...] and the HybridChunker(...) call in
chunk_documents.

In `@src/lfx/src/lfx/components/docling/chunk_docling_document.py`:
- Around line 183-187: The instantiation of HybridChunker is passing an
unsupported parameter always_emit_headings which will raise a TypeError; remove
the always_emit_headings argument from the HybridChunker(...) call (leave
tokenizer=tokenizer and merge_peers=bool(self.merge_peers)), or if you intend to
control heading inclusion, replace it with the supported parameter
include_heading_hierarchy and pass the appropriate boolean (e.g.,
include_heading_hierarchy=bool(self.include_heading_hierarchy)) so the
HybridChunker call uses only valid kwargs.

🧹 Nitpick comments (1)

src/lfx/src/lfx/_assets/component_index.json (1)

72454-72454: Unrelated dependency version bumps included in this PR.

Hunks 5–14 update google to 2.5.0 and vlmrun to 0.5.4 across multiple components. These changes are unrelated to the stated PR objective (adding merge_peers and always_emit_headings). Consider whether these should be in a separate PR for cleaner change tracking, or confirm they were intentionally bundled (e.g., via an index regeneration script).